From an unholy POV we use the reverberating and stack straight strength for more bursty hits and healing shield from necrotic strike. The pvp diamond is for overall damage and overall healing plus the extra resil. This as well as your setup should be the deciding factors of your gem build. If you are getting ran train all the time or you want to run a defensive build use the pvp gem; if you find yourself being the peeler all the time and don't take a lot of damage go for the reverberating. Not sure what frost stacks but that's the contrast between the metas for unholy; im sure its along those lines. sorry if this doesn't help

Reverberating, No question. Even as unholy where crits are not really a big deal we use it because of strength scaling. I don't play frost but frost has good strength scaling as well during pillar and is super dependent on crits so the crit damage far outpaces the resil from the meta, and strength is much better than the pvp power. Any class with auto-crit abilities wants the crit damage meta, pretty much no question. I think healers are really the only ones who want the tyrn meta anymore.

Originally Posted by Gandrake

I like how when people complain about getting killed by kill shot which can have a 43 yard range, no resource cost, and can be used again if it doesn't kill and everyone says WELL, HEY, YOU KNOW, IT IS CALLED KILL SHOT
but when a warrior does it, clearly the ability's name is "useless wet noodle piece of shit strike with an exorbitant rage cost that should do the same damage as MS"

Have a helm with each of them in, if you know a team is going to train you use the PvP meta as it offers more suitability if you're free to hit stuff use the Reverberating meta is it has more offensive pressure.